槲皮素对绵羊M Ⅱ期卵母细胞玻璃化冷冻的影响OA

This study aimed to investigate the antioxidant effects of quercetin(QUE)on sheep MII-stage oocytes during vitrification.After in vitro maturation for 24 h,sheep oocytes were randomly divided into five groups:the negative control group(fresh oocytes,without vitrifi-cation),the model group(vitrified,with 0 μmol/L QUE added to the vitrification solution),the low-dose group(vitrified,with 2.5 μmol/L QUE),the medium-dose group(vitrified,with 5 μmol/L QUE),and the high-dose group(vitrified,with 10 μmol/L QUE).After tha-wing,the oocytes from all groups were cultured in in vitro maturation medium supplemented with corresponding concentrations of QUE(0,2.5,5,and 10 μmol/L)for 0.5 h,and then the oocyte survival rate,reactive oxygen species(ROS)levels,glutathione(GSH)content,and mitochondrial membrane potential(JC-1)levels were assessed.The results showed that,compared with the negative control group,the survival rate,GSH content,and JC-1 levels were significantly decreased(P＜0.05),while the ROS levels were significantly increased(P＜0.05)in the model group,the low-dose group,and the high-dose group.However,no significant difference in the ROS levels was observed in the medium-dose group(P＞0.05).Among the vitrified groups,the low-dose and medium-dose groups significantly increased the oocyte survival rate,GSH content,and JC-1 levels(P＜0.05)and significantly decreased the ROS levels(P＜0.05),compared with the model group.In contrast,the high-dose group showed a significantly decreased survival rate,GSH content,and JC-1 levels(P＜0.05)and signif-icantly increased the ROS levels(P＜0.05),compared with the model group.In conclusion,the addition of a medium dose of QUE(5 μmol/L)during vitrification of sheep MII-stage oocytes significantly alleviated their oxidative stress,which might serve as a basis for impro-ving the efficiency of oocyte cryopreservation.